Depending on how you slice it, there are different ways to categorize hardwood flooring. The type of material (e.g., oak or walnut), the form of the material (e.g., solid or engineered), and the way the material is laid out (e.g., planks or parquet) are all ways to distinguish types of hardwood floor. Considering what kind of traffic and wear the floor will receive is key in deciding what type of hardwood floor you should use.

In terms of the type of wood, there are many hard woods that are used for hardwood floors. Perhaps the most common include maple, oak and walnut. Exotic woods like teak can also be used for hardwood flooring. A hardwood floor can also be made out of pine although pine is technically a soft wood.

In addition to the type of wood, hardwood flooring also varies in the form of the wood. That is, the wood used can be solid wood, engineered wood, or acrylic impregnated wood. Solid hardwood is just that — solid. Engineered hardwood takes thinner pieces of hardwood and layers them on top of each other alternating the grain of the layers in different directions. This cris-cross effect makes this type of hardwood floor able to withstand more weight and force. Finally, acrylic impregnated hardwood is made of a combination of solid wood and acrylic to create a stronger material that can withstand heavy traffic.

Another way to categorize hardwood floors is the size of the material and the way it is laid out. Wood can be measured in strips which are long pieces of wood that can vary in width from 1.5 inches to 2.25 inches (about 3.8 to 5.7 centimeters) in width. Planks are another style of hardwood floor. These are also long pieces of wood but they are wider than strips — at least three inches (about 7.6 centimeters) wide. Finally, parquet flooring is a little more intricate. It uses pieces of wood and configures them in a geometric pattern. A parquet floor often takes the form of small strips of wood that produce small squares in alternating directions but parquet can also have a zig-zag look among others.

Installation methods are another way to differentiate types of hardwood floor. There are types of hardwood floor that are affixed to the flooring beneath it. They can be affixed by nails, glue, or staples. Another type of hardwood floor, however, is known as a floating hardwood floor. This type of hardwood floor isn't affixed to the subfloor. A foam underlay is laid on top of the subfloor to absorb sound and protect against moisture. The pieces of hardwood are then laid on top of that. The hardwood isn't affixed to the floor however; rather the pieces are glued or snapped together in a tongue and groove fashion and the entire floor simply "floats" above the subfloor. Floating hardwood floors are often preferred because they are easy to install and generally can be installed over any surface.

How the hardwood is treated is another consideration in hardwood flooring. Wood can be stained to give it a dark or light appearance. Alternate treatments are also available such as crackling, whitewashing, or antiquing. Some hardwood floors are simply left natural or untreated.

Types of hardwood floor can vary in the finishing, or top coat, of the hardwood floor. Some hardwood floors, however, are left unfinished. Finished floors can use a top coat that simply lies on the surface or penetrates deeper into the wood. Surface finishes include urethanes and varnishes. Differences between these types of finishes involve considerations of drying time, ease in application, odor, and durability. Some finishes penetrate into the hardwood floor more than surface finishes do. These finishes require an additional coat of wax to give the surface a sheen. The sheen that the finish provides is another differentiation in hardwood flooring. There are high gloss, low gloss or satin finishes.

Many alternatives to hardwood flooring also exist. Laminate flooring, for example, uses high-density fiberboard and melamine laminate instead of wood. This product gives the appearance of a hardwood floor at a fraction of the cost.